Polyetherpolyamide elastomer comprising a hard polyamide segment, a soft polyether segment, and a polymer chain-extending dicarboxylic segment has been known.
Japanese Patent Provisional Publications No. 9-118750 and No. 2000-7780 describe polyetherpolyamide elastomer comprising a polyamide segment, a (poly)ethylene oxide segment, and a dicarboxylic segment.
Japanese Patent No. 3,199,797 describes a polyetherpolyamide elastomer comprising a polyamide segment, a polybutylene oxide segment, and a dicarboxylic segment.
According to the studies of the present inventors, the former polyetherpolyamide elastomer comprising a polyamide segment, a (poly)ethylene oxide segment, and a dicarboxylic segment shows a high water absorption, while the latter polyetherpolyamide elastomer comprising a polyamide segment, a polybutylene oxide segment, and a dicarboxylic segment is not satisfactorily high in its stress relaxation and elastic recovery percentage of elongation. The high water absorption of the elastomer is disadvantageous where the elastomer is employed for the production of articles to be used outside or under humid conditions. The relatively low stress relaxation and elastic recovery percentage of elongation is disadvantageous particularly when the elastomer is employed for the production of articles which are repeatedly bent or subjected to stress in their uses.